Cyanine type dyestuffs



Patented Dec. 9,1941

UNITED STATES PATENT OFFICE CYANINE TYPE DYESTUFFS John Davis Kendall,Ilfcrd, England, asslgnor to Ilford Limited, llford, Essex, England, aBritish company No Drawing. Application March 7, 1940, Serial No.322,834. In Great Britain March 21, 1939 12 Claims.

consists in reacting, in the presence of a strong base, a compoundcontaining the grouping CR4CR1 iRa R2 (where R1, Ra, R: and R4 arehydrogen or the hydrocarbon groupings of a cyclopentadiene homologue, orR1 and R2 may form part of an arylene residue as in indene) with aquaternary salt of a heterocylic nitrogen compound containing as areactive group a thioether or selenoether group (including an varyl-,alkylor aralkyl-thioether or -selenoether group) or a -(CH=CH)n-NH2group where n is a positive integer (including N-acyl, N-aryl andN-acylaryl substituted groups of this type (in the on or '7 position tothe quaternary nitrogen atom. The grouping -(CH=CH)NH: is hereinafterreferred to as the aminovinyl type of group.

The products obtained by this process are compounds of the followinggeneral Formula I:

where D is the remainder of a heterocyclic ring ternary ammoniumcompounds containing the and R1, R2, R3 and R4 have the meaning assignedto them above, a: is nought or 1, and 11. is nought or a positiveinteger, e. g. 1, 2 or 3.

I have found that compounds of this general structure which contain a CHgroup inthe 3 position of the cyclopentadiene grouping (i. e.'

where R1 or R4 in the above formula is hydrogen) are valuableintermediates for the production of symmetrical and unsymmetricalcyanine dyestufis.

According to the present invention, therefore,

dyestufis are produced by condensing compounds of the following generalFormula II:

C RFC R1 or R1 and R2 are part of an arylene residue as in indene, a: isnought or 1 and n is nought or a positive integer g. 1, 2 or 3 and D isthe residue of a heterocyclic nitrogen compound of the type used in theproduction of cyanine dyes),

with a quaternary salt of a heterocyclic nitrogen compound containing asa reactive group a halogen atom, a thioether or selenoether group(including an aryl-, alkylor aralkyl-thioether or -selenoether group) ora --(CH=CH)nNH2 group where n is a positive integer (including N -acyl,N -aryl and N-acylaryl substituted groups of the type), in the a or '7position to the quaternary nitrogen atom.

Compounds of the general Formula II which are used as intermediates inthe process of the present invention, may be produced by the proc-"esses described in my co-pending application Serial No. 322,835, filedMarch 7, 1940, using a cyclopentadiene or indene compound, which isunsubstituted in the 1 and 3-positions of the cyclopentadiene ring.

Any of the known types of heterocyclic quaspecified I reactive halogen,thio-ether, selenoether or amino-vinyl types of groups, commonlyemployed in the manufacture of cyanine dyestuifs may be employed in thepresent invention.

dolenines and diazines (e. g. pyrimidines), thiodiazoles andquinazolines, including the corresponding substituted and unsubstitutedpolycyclic compounds such as benzthiazoles, naphthothiazoles andanthrathiazoles and also the diazoles described in British PatentSpecification No. 425,609.

Where the quaternary salt employed contains a reactive halogen atom inthe a or '7 position to the quaternary nitrogen atom, the reaction ispreferably carried out in the presence of an acid binding agent, forexample, pyridine, ethylamine, piperidine, alkali acetate or alkalicarbonate. In other cases the reaction may be carried out inthe absenceof an acid binding agent, but in the presence of a solvent, for example,ethyl alcohol and acetic anhydride, in

which the reactants are easily soluble under the conditions of thereaction. The reaction may be readily efiected by' heating the reactantsto gether.

Instead of employing a quaternary ammo nium salt of a heterocyclicnitrogen compound containing the necessary reactive group there may beemployed the corresponding base together with an alkyl. sulphate, alkylparatoluene sulphonate or other salt which will convert the base to thenecessary quaternary salt under the conditions of the reaction. Thus, acompound of the general Formula II given above may be mixed with aheterocyclic nitrogen base containing one of the reactive groupsreferred to above-and with an alkyl paratoluene sulphonate or alkylsulphate'and the mixture fused. In this case the product obtained is aparatoluene sulphonate or alkyl sulphate and it may be converted to thecorresponding allnvl halide by dissolving it in ethyl alcohol and addingan aqueous solution of an alkali halide.

The mechanism of the general reaction on which the present invention isbased may be illustrated by the reaction between 1-methyl-1:2-dihydrobenzthiazolylidene indene and l-w-acetanilido-vinyl-lz3z3-trimethyl-indolenium iodide,

The process of the invention is illustrated by the following specificexamples:

Example I 0.61 gm. of l-methylthiolbenzthiazole and 0.62

gm. of methyl-p-toluene sulphonate' were mixed together and heatedfor'two hours at 130-140 C. 0.48 gm. ofl-w-N-methyldihydrobenzthiazolylidene ethylidene indene and 5 ccs. ofpyridine were then added and the mixture warmed on a water bath untilall the solids dissolved. The mixture was then refluxed gently fortwenty minutes during which time a blue colour developed. The mixturewas then poured into a solution of potassium bromide when the dyestufi4.46 gms. of 2-o-acetanilidovinyl-lz3z3-trimethylindolenium iodide, 4cos. of indene, 10 cos. of pyridine and 4 cos. of diethylamine weremixed together and boiled under a reflux condenser for one hour. Theexcess pyridine was removed by distillation in vacuum and the solidquaternary salt prepared by reacting 8.62 gms. ofl-methylthiolbenzthiazole and 8.72 gins. of methyl-p-toluene sulp'honatewas added to the residue, and then 20 cos. of alcohol were added.

The mixture was refluxed for one hour and poured into a potassium iodidesolution. The precipitate was filtered oil, washed with ethyl alcoholand ether and recrystallized from 30 cos. of methyl alcohol. The productconsisted of dark green needles, melting at 2'19 C. with decomposltion.

This dyestufi incorporated in asilver chloride aaeaeoa emulsion impartsa band of sensitivity between 5600-7000 A.

Example III The dyestufi' produced as set forth in Example 11 may alsobe produced by the' iollowing method: 1 v

1.81 gms. o! l-methylthiobenzthlazoleand 1.86

gms. of methyl-p-toluene sulphonate were mixed together and heated in anoil bath at 130-140 C. for 2 hours. The mixture was cooled and there wasadded 1 cc. of indene. 3 cos. of diethylamine and 15 ccs. of pyridine.This mixture was heated on a water bath for five minutes and thenvrefluxed for two hours, during which a yellowbrown colour developed. Themixture was then poured into a warm solution of 3 ms. of potas-'- siumiodide and in 10 cos. of water. Benzene was added and the mixturefiltered. The benzene layer was then separated the benzene dis-' tilledoil. and the residue warmed under vacuum to remove indene and Pyridine.The residue was then extracted with ether, the ether solution decantedand the ether removed by distillation. To

the residue was then added 2.23 gins. of 1:3:3-

Example IV 0.83 gm. of l-methylthiol-benzoxazole, 0.93 gm. ofmethyl-p-toluene sulphonate and 0.72 gm. of 1 a:-(N-methyldihydrobenzthiazolylidene) ethylidene indene were mixedtogether and fused at 130-140 C. for two-and-a-half hours. During thistreatment a blue colour developed and solid separated. 5 cos. ofpyridine were-added and the mixture heated on a water bath for ten 7minutes and. then gently refluxed for ten minutes.

matter removed by filtration. The-solid matter was washed with ethylalcohol and ether and consisted of a dyestufi having a. melting point ofC. V .I This dyestufl incorporated in a silver chloride emulsion impartsa. band of sensitivity between 5600-6800 A. 7

Example V 0.88 gm. of l-o-acetanilidovinyl-benzoxazole methiodide,0.48gm. oi l-w- (N-methyl dihydro- .benzthiazolylidene) -ethylideneindene and 15 cos. of acetic anhydride were mixed together and heated ona water bath for five minutesand then boiled for five minutes. Thedyestufi precipitated from the-hot solution.- The solutionwas thencooled and the dyestuff separated by 0.9 gm. of l-acetanlidovinylbenzoxazole ethiodide, 0.48 gm. of l-w-(N-methyldihydro- The mixture Therecrystallised .prod- The mixture was cooled and the solid'drobenzthiazolylidene-ethylidene Example VII 1.13 gm. of1-w-acetanilldovinyl-benzthiazole ethiodide, and 0.72 gm. ofl-w-(N-methyldihyindene were mixed together and finely ground. Thefinely ground mixture was then heated with 30 cos. of acetic anhydridefor five minutes on a water bath and the mixture then gently refluxedfor ten minutes. The dyestufi precipitated from the hot solution and wasremoved by filtration.-

washed with acetic anhydride, hot benzene ethyl Example VIII 0.61 gm. of2-w-acetanilidovinyl-l:3z3-trimethyl-indolenium iodide (finely ground),0.36 gm. of 1 w (N-methyldihydrobenzthiazolylidenel-ethylidene indeneand 20 ccs. of acetic anhydride were mixed together and heated on awater bath for two minutes. The mixture was then heated over a flame forfive minutes until it just boiled and was allowed to boil for a shortperiod. The dyestufi precipitated out for the hot solution. The solutionwas cooled and the dyestufi removed by filtration. The dyestuff was thenwashed with acetic anhydride, hot benzene, ethyl alcohol and ether andconsisted of dark'bronze crystals melting at 271 C. with decomposition.

Example IX 1.8 gm. of 'l-methylthiol-benztluazole and 1.86 gm. ofmethyl-p-toluene sulphonate were mixed together and heated forthree-and-a-half hours at 130 C. 1 cc. of indene, 3 ccs. of diethylamineand cos. of pyridine were then added to the mixture. The mixture washeated under reflux for two hours during which period a yellow-browncolour-developed. The mixture was poured into 30 cos. of a 16% potassiumiodide solution. Benzene was added and the solution filtered. Thebenzene layer was separated and the aqueous layer extracted twice withbenzene. The benzene layer and benzene extracts were the mixed togetherand dried over anhydrous potassium carbonate. The benzene was thenremoved ;by distillation and the residue heated in vacuum to removepyridine and indene.

The residue, which was of an oily character, was thenextracted withether, and the ether' exintense blue colour developed. The mixture wasthe residue washed with alcohol and ether.

tract dried'over potassium carbonate. The ether was then removed byevaporation and 2.23 gm. of 2-w-acetanilidovinyl-1 :3 3-trimethylindolenium iodide and 20 cos. of acetic anhydride added to the residue.

The mixture was warmed on a water bath for five minutes and then heatedfor a quarter-ofan-hour over a flame. During this treatment an thentransferred to abeaker and cooled. The solid matter was separated byfiltration and washed with acetic anhydride, hot benzene, ethyl alcohol,etherand warm water. The solid matter was then recrystallised frommethyl alcohol yielding a dyestufl having a melting point of Example X3.62 gm. of l-methyl-thiolbenzthiazole and 3.72 gm. of methyl-p-toluenesulphonate were mixed together and heated ,in an oil bath for threehours at 130 C. 2 ccs. of indene, 8 cos. of diethylamine and 30 cos. ofpyridine were added to the cooled mixture and the mixture was thenheated on a water bath for five minutes and then refluxed for two hoursat C. The.

solution was then poured into a solution of 4 gm. of potassium iodideand 15 cos. of water. Benzene was added and the mixture filtered. Thebenzene layer was then separated, the aqueous layer was extracted withbenzene and the benzene extracts were bulked together and dried overpotassium carbonate. The solution was then filtered and the solventremoved. The residue was then dried in a vacuum desiccator.

' 1.15 gms. of l-methyl thiol-a-naphthathiazole and 0.93 gm. ofmethyl-p-toluene sulphonate were mixed together and heated for threehours at -140 C. To the cooled product was added 1.14 gms. of theresidue obtained according to the preceding paragraph dissolved in 15cos. of alcohol. The mixture was then heated on a water bath for onehour during which a reddish-yellow colour developed. The mixture wasthen poured into potassium bromide solution and after cool-- Example XI0.83 gm. 6r l-methylthiolbenzoxazole and 0.93 gm. of methyl-p-toluenesulphonate were mixed together and heated for three hours at 130 C.

The mixture was then cooled and to it there was added 1.4 gms. of theresidue produced according to the first paragraph in Example X,dissolved in 15 ccs. of alcohol. The mixture was then heated on a. waterbath for one hour during which a yellowish-orange colour developed. Themixture 'was poured into potassium iodide solution whereupon an oilseparated out. This oil was triturated with benzene, the benzenesolution was decanted and the residue treated with hot alcohol. Thesolution was cooled, filtered, and The product was obtained as greencrystals having a melting point of 213 C. with decomposition.

In the following claims the expressions thio-- ether group, seleno-ethergroup" and aminovinyl type of group have been used for the sake ofbriefness, but it is to be understood that the first two of theseexpressions include the corresponding aryl-, alkyl-, andaralkylthio-ether and -seleno-ether groups and that the third expresSionincludes groups of the formula (where n. is a positive integer) andN-acyl, N-aryl and N-aoylaryl substituted groups of this type.

I claim: 1. Process for the production of dyestufls,

which comprises condensing a compound of the general tormula:

wherein R1 and R2 are selected from the group consisting of hydrogenatoms, hydrocarbon groups and the atoms necessary to complete an aryleneradicalwith C'=C'--, R3 is selected from the group consisting ofhydrogen atoms and hydrocarbon groups, X is selected from the groupconsisting of nought and 1, n is selected from the group consisting ofnought and positive integers, and D constitutes the atoms necessary toform a heterocyclic nitrogen compound of the type used in the productionof cyanine dyes, with a quaternary salt of a heterocyclic nitrogencompound of the type used in the production of cyanine dyes containingin one of the a and -y positions to the quaternary nitrogen atom areactive group selected from the group consisting of the thioethergroup, the seleno ether group, the amino-vinyl type of group, and ahalogen atom.

2. Process for the production of dyestuffs which comprises condensing acompound of the general formula:

alkyl CRs= H wherein R1 and R2 are selected from the group consisting ofhydrogen 7 atoms, hydrocarbon groups and the atoms necessary to completean from the group consisting of hydrogen atoms and hydrocarbon groups, Xis selected from the group consisting-of nought and 1, and D constitutesthe atoms necessary to form a heterocyclic nitrogen compound of the typeused in the production of cyanine dyes,'with a quaternary salt of aheterocyclic nitrogen compound of the type used in the production ofcyanine dyes, but different from the heterocyclic nitrogen compoundcontaining D, containing in one of the a and 7 positions to thequaternary nitrogen atom a reor the type used in the production orcyanine dyes containing in one of the a and 7 positions to thequaternary nitrogen atom a reactive group selected from the groupconsisting of the thio-l ether group the seleno ether group, theaminovinyl type or group, and a halogen atom.

4. Process for the production of dyestufis, which comprises condensing acompound of the general formula:

IiI(CH=CH)=-=O alkyl CR1=CH wherein R1 and R2 are selected from thegroup consisting of hydrogen atoms, hydrocarbon groups and the atomsnecessary to complete an arylene radical with C'=C', R3 is selected fromthe group consisting of hydrogen atoms and hydrocarbon groups, :1: isselected from the group consisting of nought and 1, and D constitutesthe atoms necessary to form a heterocyclic nitrogen compound of the typeused in the production of cyanine dyes, with a quaternary salt of aheterocyclic nitrogen compound or the type used in the production ofcyanine dyes containing in one of the u and '7 positions to thequaternary nitrogen atom a reactive thioether group.

5. Process according to claim 1 wherein the said quaternary salt of'aheterocyclic nitrogen compound is formed in situ by employing the activegroup selected from the group consisting atom.

3. Process for the production of dyestufls, I

which comprises condensing a compound of the general formula:

' D om=cm i icir=on ,-b(=on-cn)..=o i lik i on== H wherein R1 and Ra-areselected from the group consisting of hydrogen atoms, hydrocarbon groupsand the atoms necessary to complete an arylene radical with C'=C', R; isselected from the group consisting of hydrogen atoms and hydrocarbongroups, a: is selected from the group consisting of nought and 1, n is apositive integer and D constitutes the atoms necessary to form aheterocyclic nitrogen compound of the type used in the production ofcyanine dyes, with a quaalkyl salt and effecting the condensation toproduce the dyestufl by fusing the three reagents together.

arylene radical with --c'=c'-, R3 is selected 35 6. A dyestufi of thegeneral formula:

wherein Y is an acid radical, R1 and R2 are selected from the groupconsisting of hydrogen atoms, the hydrocarbon groups and the atomsnecessary to complete an arylene radical with I alkyl Y wherein Y is anacid radical, R1 and R: are selected from the group consisting ofhydrogen atoms, hydrocarbon groups and the atoms necessary to completean arylene radical with -C'=C'-, R3 is selected from the groupconsisting of hydrogen atoms and hydrocarbon groups, a: is selected fromthe group consisting of nought and 1 and Di and D2 constitute the atomsternary salt of a heterocyclic nitrogen compound 7 1-. Nmethyldihydrobenzthiazolylidine ethylldene indene withl-methylthiolbenzthiazole and an alkyl salt.

9. The process which comprises condensing 1-0: Nmethyldihydrobenzthiazolylidine ethylidene indene withI-methylthlolbenzthiazole and methyl-p-toluene sulphonate in thepresence of an acid binding agent.

10. A dyestufl of the general formula:

5 anhydride.

12. A dyestufl or the general formula:

JOHN DAVID KENDALL.

CER'IPIFICATE OF CORRECTION.

Patent No. 2,265,909, December 9, 19151.

JOHN DAVID KENDALL.

It is hereby certified that error appears in the printed. specificationof the above nzimbered patent requiring correction as follows: Page 2,second column, line '8, for "metmglthiobenzthiazole" read --methlthiolbenzthiazole-; and line 72, after "A." insert --with amaximum atabout"(5001. page 5, first column, line 17, for"drcbenzthiazolylidene-ethylidene" read--drobenzthiazolylidene)-ethylidene-; line k0, for "out for" read -outfrom--; line 62, for "the" read --then-; page 14., second column, line1414.,

claim 6, strike out "the" first occurrence, and line 55, for '"n" read--in-;

and that the said Letters Patent should be read with this correctiontherein that the. same may conform to the record of the case in thePatent Office.

Signed and sealed this 10th day of Febru xar'y, A. D. 1912.

Henry Van Arsdale, (Seal) Acting Commissioner of Patents.

